KR20100100165A - Slab top-down method of underground construction - Google Patents

Abstract

PURPOSE: A reverse direction construction method of an underground structure is provided to reduce production times and costs by the formation of a slab on concrete. CONSTITUTION: A reverse direction construction method of an underground structure comprises following steps. An underground continuous wall is formed on an underground position where an underground outer wall will be formed, so that an underground outer line may be formed(S10). Multiple center piles are built in the surface divided by the underground continuous wall, so that a base frame of a post is formed(S20). Two or more slabs forming the bottom surface of each under layer are laminated to move along multiple center piles(S30).

Description

Slab top-down method of underground construction

The present invention relates to a method for constructing an underground structure, and more particularly, the underground structure is constructed from the top to the bottom direction, and is formed by stacking a plurality of slabs to be spaced apart from each other, and excavating the lower side of the slab to a required depth. By moving the laminated slab downwards, the installation can reduce the work process, reduce the working time, reduce waste by reducing the process, and reduce the cost, thereby improving the work efficiency. The present invention relates to a reverse construction method of underground structures.

In general, various techniques are used in the construction of the basement, but among them, the earthquake wall method includes a thumb pile earth wall, a sheet pile, a cast-in-place concrete pile, and a diaphragm wall (aka slurry wall) method.

In addition, earth wall support methods include Earth Anchor (tension anchor support method), Strut method (compression brace support method), SPS method (Permanent Structural Members As Temporary Strut), IPS method, SLS method, etc. Foreground, general formwork, medal formwork and deck plate are used.

Here, the strut wall support method such as strut type is a temporary structure to support earth pressure before the permanent structure is constructed. It is not only an obstacle for the excavation and framing work in the basement layer, but also needs to be dismantled after the construction of the structure. It is a factor that causes problems such as deterioration and increase of construction date.

In order to solve this problem, the reverse casting method is used. The reverse casting method is a permanent structure constructed by constructing the underground permanent structure from the upper side to the lower direction and at the required position. It is a method of supporting hydraulic pressure and earth pressure.

In order to construct a permanent structure with a back ground, this reverse casting method must perform formwork, reinforcing work, concrete pouring work or steel frame assembly and installation work in a closed space underground. There is a problem in that productivity is greatly reduced due to transportation, working conditions, and the like.

In addition, before the cast concrete was cured and secured the required strength (usually 28 days), the excavation work was impossible at the bottom, which required the construction cost to be increased and the construction period to be long.

Recently developed SPS method started from the concept of supporting the earth pressure and hydraulic pressure acting on the underground continuous wall only with steel frames and pillars permanently used in the building, but the earth pressure acting underground with the skeleton type formed only of steel beams and columns among the underground structures. And insufficiently to cope with hydraulic pressure.

In order to overcome this problem, the earth pressure and water pressure are supported by the slab constructed by using the deck plate after installing the basement steel frame. It has become a deformed form, and many problems occur because steel frame assembly work, field welding work, deck plate installation work, reinforcement work, concrete placing work, etc. must be performed in an enclosed space underground.

In order to solve the above problems, the present invention is to construct an underground structure by a reverse method, but to form a stack so that each layer of the slab can be separated from each other, and to excavate the lower ground of the slab to a certain depth Moving and installing the slab reduces the workflow and time.

In particular, it is possible to reduce the production period and production cost by forming the slab on the formwork cast-away concrete placed on the ground without a separate formwork or club.

In addition, the slab constituting each layer is moved downward to support the earth pressure and water pressure of the continuous wall of the underground can be omitted the use of reinforcement members such as conventional temporary construction materials and steel frame.

And by forming a part of the slab openings for carrying out materials, earth and sand equipment, when the ground is excavated, the excavation is easy as the excavation is made through the open slab, it is possible to reduce the occurrence of noise and dust conventionally generated.

Accordingly, in the construction of underground structures, it is an object to provide a reverse construction method of underground structures that can improve the work efficiency because the process and time can be reduced and the cost can be reduced than before.

In order to achieve the above object, the present invention provides an underground continuous wall forming step of forming an underground outer line by forming an underground outer continuous wall at an underground location in which an underground outer wall is to be formed, and a plurality of center piles on the ground partitioned by the underground continuous wall ( a center pile construction step of forming a base frame of the pillar by constructing a center pile, a stacking slab forming step of stacking at least two slabs which form a bottom surface of each basement layer to be moved along the plurality of center piles; And moving the plurality of stacked slabs to the lower side, each slab is installed in the position of each layer, including the slab installation step is repeatedly carried out the ground excavation and slab downward movement and installation.

Preferably, in the laminated slab forming step, the number of formation of the slab is determined according to the number of layers to be formed, and is laminated between the slabs so as to be separated from each other by a peeling member.

After the excavation and flattening of the ground downward so that the upper surface of the slab located at the top of the plurality of slabs horizontal with the ground, the cast concrete is cast on the excavated ground to form the plurality of slabs.

In addition, the release member is at least one selected from a release agent, vinyl and a film.

A fixing hole is passed through the slab so that the center pile is penetrated, and a reinforcing frame is further provided inside the inner surface of the fixing hole, and the reinforcing frame is formed so that the shape of the upper end and the lower end is symmetrical.

In addition, when the reinforcement member or the deflection prevention member is arranged in a checkered shape in the interior of the slab is separated from any one of the sensor pile of the slab fixed to a plurality of center piles when the support force is lost, The deflection prevention member is supported by another adjacent center pile to prevent the deflection of the slab.

And the slab installation step, the slab fixing step for fixing the slab located at the top of the plurality of slabs formed in the slab forming step to the underground continuous wall and the center pile, excavating the lower ground of the plurality of formed slabs more than one layer deep Ground slab excavation step, and a slab movement step of moving the lower side of the slab that is not fixed in the slab fixing step is moved downwardly spaced at a height interval with the fixed slab, the slab fixed The step, the ground excavation step and the slab movement step are repeated.

In addition, in the slab fixing step, the inner surface of the slab fixing hole through which the center pile is penetrated is formed to be inclined outward toward the lower side, the center pile is provided with a fixing piece having an outer surface to correspond to the inner surface of the fixing hole. And the edges of the slab are cast by the underground continuous wall and concrete.

And it is more firmly fixed using reinforcing bars and concrete or grouting around the fixing hole and the fixing piece of the slab.

In the slab fixing step, the center pile and the slab are fixed by welding using a bent center fixing plate, which is fixed to at least one selected from an upper surface and a lower surface of the slab, and the center fixing plate is provided. The outside of the center pile is fixed by concrete.

And the side of the edge of the slab is provided with a fixing bolt protruding outward or connected to the inner reinforcement of one or more reinforcement bar is provided, and the end of the reinforcing bar or high information contact the continuous wall, As fixed by concrete or the like, the side surface of the slab is fixed to the continuous wall.

In addition, the side end portion of the slab is further provided with a side fixing plate connected to the top or the bottom so as to be rotatable, when casting concrete, serves as a formwork.

And the ground excavation step is formed to open and close a portion of the formed slab, and opens a portion of the slab to excavate the lower ground.

In addition, in the slab movement step, there is further provided a section that is expanded and contracted by the gas between the laminated slab and the excavated ground.

As described above, according to the reverse construction method of the underground structure according to the present invention, there is no need for a separate formwork, quality control is easy, waste generation is reduced by shortening the work process, environmentally friendly, each laminated slab It is possible to work in winter and rainy season because there are few parts exposed to outside air at the time of formation, so all weather construction is possible.

In addition, when the laminated slab is formed, each slab can be formed quickly and continuously as the bottom slab is supported by the ground, and a separate soil film supporting hypothesis is provided as the lowered slab supports the earth pressure and water pressure acting on the underground continuous wall. Construction of structures or steel golbo can be omitted.

Due to the lowered slab, the frame structure of the underground structure can be flat plate or flat slab type, and the height of the excavated earth excavation is reduced due to the reduced height compared to the conventional structure. In this case, since the amount of rock rupture is minimized, it is a very useful and effective invention that can reduce the cost and shorten the working time than before, thereby improving work efficiency.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

In addition, the present embodiment is not intended to limit the scope of the present invention, but is presented by way of example only, and various modifications may be made without departing from the technical gist of the present invention.

1 is a view showing a flow chart of the reverse construction method of the underground structure according to the present invention, Figure 2 is a view showing a flow chart of the slab installation step of the reverse construction method of the underground structure according to the invention, Figure 3 4 is a view showing a reverse construction method of the underground structure according to the invention, Figure 4 is a view showing the ground excavation of the reverse construction method of the underground structure according to the present invention, Figure 5 is a reverse construction method of the underground structure according to the present invention Figure 6 is a view showing the installation and movement of the slab, Figure 6 is a view showing a slab fixing method of the reverse construction method of the underground structure according to the present invention, Figure 7 is a slab fixing of the reverse construction method of the underground structure according to the present invention. 8 is a view showing another embodiment of the method, Figure 8 is a view showing a slab sag prevention member of the reverse construction method of the underground structure according to the invention All.

As shown in the figure, the reverse structure construction method of the underground structure is composed of the underground continuous wall forming step (S10), the center pile construction step (S20), the laminated slab forming step (S30) and the slab installation step (S40).

Underground continuous wall forming step (S10) is to form a continuous underground wall 100 in the underground position where the basement outer wall is to be formed, thereby forming a basic outer wall of the underground structure.

And the center pile construction step (S20) is to build a plurality of center piles (center pile: 200) at a predetermined interval in the ground between each underground continuous wall (100) where the column is to be constructed.

In this case, the number of center piles 200 to be built is more than the number of slabs 200 required to support the slab 300, and the space can be secured by removing the slab 300 after descending.

Stacking slab forming step (S30) is to be formed by stacking at least two slabs 300 forming the bottom surface of each basement layer to be moved along a plurality of center piles 200, according to the number of basement layers to be formed The number of slabs 300 is determined.

And between each of the slab 300 to be stacked is formed to be separated from each other by the peeling member 400, each of the slab 300 through the fixing hole 310 to pass through the center pile 200.

The peeling member 400 is used as any one or more selected from a release agent, vinyl and a film, and can be used as long as it can peel each slab 300.

In addition, after excavating and flattening the ground to the lower side so that the upper surface of the slab 300 located at the top of the plurality of slabs 300 of the laminated slab forming step (S30) to be horizontal with the ground, discarded concrete for formwork on the excavated ground By pouring a plurality of slabs 300 to form.

In other words, the number of slabs 300 to be formed is determined and the ground is excavated to a predetermined depth, and then the cast-away concrete is poured, and each slab 300 is laminated on the cast-away concrete.

As such, when a plurality of slabs 300 are formed, the slab 300 is exposed to outside air so that all-weather construction is possible even in winter, and the lowermost slab 300 is formed by cast concrete and the ground. As it is supported, it is possible to form each slab 300 continuously even before the slab 300 obtains the concrete strength.

And in the slab installation step (S40) by moving a plurality of slabs 300 formed to the lower side, by installing each slab 300 in the position of each floor, ground excavation and slab 300 downward movement and installation repeatedly Will be done.

This slab installation step (S40), as shown in Figure 2, consisting of a slab fixing step (S41) and the ground excavation step (S42) and the slab moving step (S43), the slab fixing step (S41) and the ground excavation step (S42) and the slab movement step (S43) are repeated.

3 to 7, the slab fixing step (S41) is the slab 300 located at the top of the plurality of slabs (300) formed in the slab forming step (S30), the underground continuous wall 100 and the center pile It will be fixed to (200).

And in the ground excavation step (S42) is to excavate the bottom surface of the slab 300 formed a plurality of more than one layer depth, in the slab movement step (S43) a plurality of slabs 300 not fixed in the slab fixing step (S41) The uppermost slab 300 is moved downward so as to be spaced apart from the fixed slab 300 by one layer height interval.

Laminated slab 300 moved to the lower side again, after the slab fixing step (S41) of the uppermost slab 300 is fixed to the underground continuous wall 100 and the center pile 200, the ground excavation step (S42) ) And the slab moving step (S43) again.

At this time, in the slab fixing step (S41), the inner surface of the slab fixing hole 310 through which the center pile 200 penetrates is formed to be inclined outward toward the lower side, and the inner side of the fixing hole 310 in the center pile 200. A fixing piece 600 having an inclined outer surface to be inclined with each other is provided and fixed as being fitted together, as shown in FIG. 8.

This is because it can omit the use of a separate reinforcing member used in the process of forming each slab 300 after the conventional excavation, it is possible to shorten time and reduce costs.

And, as shown in Figure 9, the fixing of the slab 300 is fixed by the reinforcing bars 610 and concrete or grouting in the state in which the fixing hole 310 and the fixing piece 600 of Figure 8 is applied ( Between 310 and the fixing piece 600 may be more firmly fixed.

In addition, it is preferable that the edge portion of the slab 300 is fixed by being poured by the underground continuous wall 100 and concrete.

At this time, the fixing hole 310 of the slab 300 is passed through, the inner side of the fixing hole 310 is further provided with a reinforcement frame 320, the reinforcement frame 320 so that the shape of the upper end and the lower end is symmetrical Is formed.

In other words, the reinforcement frame 320 is formed of a shape such as 'c' or 'H' and 'I', and may be any shape if the upper and lower portions are symmetrical.

The reinforcement frame 320 is to reinforce the periphery of the fixing hole 310 of the slab 300, it will be reinforced so that the slab 300 can be more firmly fixed to the center pile (200).

Meanwhile, as shown in FIG. 10, in the slab fixing step S41, the slab 300 may be fixed to the center pile 200 by welding, using the bent center fixing plate 700, and the center fixing may be performed. The plate 700 may be fixed to at least one selected from the upper and lower surfaces of the slab 300 to fix the center pile 200 and the slab 300.

The center fixing plate 700 is provided along the connection portion of the center pile 200 and the slab 300, and may be further fixed by a separate fixing pin, and the center pile provided with the center fixing plate 700 ( The outside of 200 is preferably finished by pouring concrete.

In addition, as shown in Figure 11, the edge side of the slab 300 is provided with one or more reinforcing bars 340 is protruding outwardly or is connected to the reinforcing bars 340 is provided with a fixing bolt 350 protruding outwards do.

After the end of the reinforcing bar 340 or the fixing bolt 350 is in contact with the underground continuous wall 100, the side of the slab 300 is fixed with the underground continuous wall 100 as it is poured and fixed by concrete or the like.

And, as shown in Figure 12, the side end portion of the slab 300 is further provided with a side fixing plate 710 is connected to the top or the bottom so as to be rotatable, when pouring concrete, it is preferable to serve as a formwork.

In addition, as shown in FIG. 13, the slab 300 is further provided with a deflection preventing member 800 in which the tensile reinforcing bar or tensile steel wire is arranged in a checkered shape.

The sag prevention member 800 is a sag prevention member 800 when the slab 300 is separated from any one of the slab 300 fixed to the plurality of center piles 200 and the bearing force is lost. ) Is supported by another adjacent center pile 200 to prevent sagging of the slab 300.

On the other hand, a part of the slab 300 is formed in the opening portion 330 for the material, soil and equipment in and out, and the excavation work is made through the opening 330 of the slab 300 in the ground excavation step (S42). do.

When the excavation work is performed through the opening 330 of the slab 300, the dust generated during the conventional excavation may be prevented from being polluted as it is diffused into the air, thereby enabling environmentally friendly excavation work.

And in the slab movement step (S43) that the slab 300 is moved to the lower side by a separate slab lowering device 500, the slab lowering device 500 if the slab 300 can be easily moved to the lower side It can be used without limitation.

In the present invention, the slab lowering device 500 is preferably used to move the slab 300 along the longitudinal direction of the center pile 200.

On the other hand, as shown in Figure 14, between the lower slab 300 of the stacked slabs and the excavated ground is further provided with a cushion portion 510 which is expanded and contracted by the gas is the descending speed of the slab 300 To adjust the, it is possible to prevent the slab 300 is inclined to one side.

The cushion unit 510 is preferably expanded and contracted using air, and may be installed in the entire lower side of the slab 300 or may be provided in a part where load is concentrated.

Such a reverse construction method of the underground structure can solve the conventional problems such as reducing the process and the time can be reduced compared to the conventional cost can provide an innovative underground structure construction method.

1 is a view showing a flow chart of the reverse construction method of the underground structure according to the present invention,

Figure 2 is a view showing a flow chart of the slab installation step of the reverse construction method of the underground structure according to the present invention,

3 is a view showing a reverse construction method of the underground structure according to the present invention,

4 is a view showing the ground excavation of the reverse construction method of the underground structure according to the present invention,

5 is a view showing the slab installation and movement of the reverse construction method of the underground structure according to the present invention,

6 is a view showing a slab fixing method of the reverse construction method of the underground structure according to the present invention,

7 is a view showing another embodiment of the slab fixing method of the reverse construction method of the underground structure according to the present invention,

8 is a view showing a slab sag prevention member of the reverse construction method of the underground structure according to the present invention.

<Description of Symbols for Main Parts of Drawings>

100: continuous continuous wall 200: center pile

300: slab 310: fixing hole

400: peeling member 500: slab lowering device

600: fixed piece 610: rebar

800: sag prevention member

Claims (14)

An underground continuous wall forming step of forming an underground outer line by forming an underground continuous wall in an underground position where an underground outer wall is to be formed; Center pile construction step of forming a plurality of center pile (center pile) on the ground partitioned by the underground continuous wall to form the base frame of the pillar; A laminated slab forming step of stacking at least two slabs forming a bottom surface of each basement layer so as to be moved along the plurality of center piles; And Moving the plurality of stacked slabs to the lower side, each slab is installed at the position of each layer, the ground construction method of the underground structure comprising a slab installation step of repeatedly excavation and downward movement and installation of the ground. The method of claim 1, wherein in the forming of the laminated slab, The number of formation of the slab is determined according to the number of layers to be formed, the reverse construction method of the underground structure, characterized in that the lamination is formed between each slab by the separation member to be separated from each other. The method of claim 2, After excavating and flattening the ground downward so that the upper surface of the slab located at the top of the plurality of slabs horizontal to the ground, and then cast the formwork for cast concrete on the excavated ground to form the plurality of slabs Reverse construction method of underground structure. The method of claim 2, The peeling member is a reverse construction method of the underground structure, characterized in that any one or more selected from the release agent, vinyl and film. The method of claim 2, A fixing hole is passed through the slab so that the center pile is penetrated, and a reinforcing frame is further provided inside the inner surface of the fixing hole, and the reinforcing frame is formed such that the upper and lower ends thereof are symmetrically formed. Construction method. The method of claim 2, The slab is further provided with a deflection preventing member in which the reinforcing bars or the tensile steel wires are arranged in a checkered shape in the slab. A method for constructing a reverse structure of an underground structure, characterized by preventing the slab from collapsing as the preventing member is supported by another adjacent center pile to prevent sagging. According to claim 1, The slab installation step, A slab fixing step of fixing the slab located at the top of the plurality of slabs formed in the slab forming step to the underground continuous wall and the center pile; A ground excavation step of digging the lower ground of the plurality of formed slabs more than one layer deep; And Including the slab movement step of moving the lower side of the slab that is not fixed in the slab fixing step is moved downwardly spaced at a height interval with the fixed slab, Reverse construction method of the underground structure, characterized in that the slab fixing step, the ground excavation step and the slab movement step is repeated. The method of claim 7, wherein in the slab fixing step, The inner surface of the slab fixing hole through which the center pile is penetrated is formed to be inclined outward toward the lower side, the center pile is provided with a fixing piece having an outer surface to correspond to the inner surface of the fixing hole, The edge of the slab is the reverse construction method of the underground structure, characterized in that the pouring by the underground continuous wall and concrete. The method of claim 8, Reverse construction method of the underground structure, characterized in that more securely fixed using reinforcing bars and concrete or grouting around the fixing hole and the fixing piece of the slab. The method of claim 7, wherein in the slab fixing step, The center pile and the slab are fixed by welding using a bent center fixing plate, and fixed to any one or more selected from the upper and lower surfaces of the slab, The reverse construction method of the underground structure, characterized in that the outer side of the center pile provided with the center fixing plate is fixed by concrete. The method of claim 8 or 10, The side of the edge of the slab is provided with a fixing bolt protruding outward or connected to the one or more reinforcing steel bar is protruded outward, And the side of the slab is fixed to the continuous wall as the end of the reinforcing bar or the high information contact with the continuous wall, and is fixed by concrete or the like. The method of claim 11, The side end portion of the slab is provided with a side fixing plate connected to the top or the bottom so as to be rotatable further when building concrete, reverse construction method of the underground structure, characterized in that serves as a formwork. The method of claim 7, wherein the ground excavation step, And forming a part of the formed slab so as to be openable and open, and opening a part of the slab to excavate a lower surface thereof. The method of claim 7, wherein in the slab movement step, And a cushion part further expanded and contracted by a gas between the stacked slabs and the excavated ground.

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